1. Technical Field
Exemplary embodiments of the inventive concept relate generally to a successive approximation register analog-digital converter (SAR ADC), more particularly to an apparatus and a method for converting an analog signal into n-bit digital data in which a more exact clock period can be implemented.
2. Discussion of Related Art
An Analog-to-Digital Converter (ADC) is a device for converting an analog signal to a digital code or digital signal. The ADC samples the analog signal to convert the analog signal into the digital code or digital signal corresponding to a magnitude of the analog signal.
A Successive Approximation Register ADC (SAR ADC) is a type of ADC that combines digital codes with each other while sequentially increasing or decreasing the digital codes from the most significant bit and compares the digital codes with an analog signal, so that a digital code is approximated to the analog input signal.
In a general SAR ADC, a clock signal required for a binary searching operation section is received from a source outside the ADC. In an asynchronous SAR ADC, a clock signal for the binary searching operation section is generated inside the ADC.
However, when the clock signal generated from inside the asynchronous SAR ADC, it is difficult to implement an exact clock period required for the binary searching operation section of the SAR ADC.